Suspension clamp



Juy 10, 1934., R. L. MccoY SUSPENSION CLAMP Filed Dec. lJ 1930 i0 l 50a Patented July 1G, 1934 NITE` STATES PATENT OFFICE SUSPENSION CLAMP Robert L. McCoy, Baltimore, Md.'y assigner to Locke Insulator Corporation, Baltimore, Md., a corporation of Maryland The invention relates to supporting devices for transmission lines and has special reference to conductor clamps.'

It is well known that various types ofV clamps 5 have been used for the purpose 'of supporting the conductors of transmission lines, most types being of the rigid variety while others are designed to release their grip and open up in the event of unbalanced longitudinal strain upon the conducton,l Ordinarily clamps or either variety are hung at the lower ends of strings of insulators which are capable of limited swinging movement. It is a fact thata suspended cable is never still and that it sways with a combination of movelo ments which bring about bending strains at the ends of the clamp, the result being that, unless the conductor be armored by some suitable special equipment, the outer strands of the cable break, bringing about a condition which is highly of installations,I it is highly desirable that the holding power of the clamp be controlled within 'close limits. Clearly this entails an accurate construction whiclris not only difficult to attain but also expensive o account of the care and time required to shap and fit the clamp parts with precision. In some instances it is desirable that the degree of holding action be capable of variation for some reason or other. Another porting conductors of diierent diameters clamps of diierent sizes are necessary, thereby necessitating that the manufacturer keep on hand a line of clamps of dierent sizes at least in so far as regards the conductor receiving channels or glOOVeS;

-Tt is with all of the above facts in view that I have devised the present invention which has for its general object the provision of a novel clamp in which the cable, while being restrained from longitudinal movement, is capable of other movements with respect to the clamp so as to avoid the bringing about of the highly objec tionable bending strains upon the cable resulting from movements thereof. I

An important object of the invention is to provide a clampembodying what may be called a stirrup or cradle-like supporting member within which isloosely confined a stopmember in the form of a separable .block which is clamped directly upon the conductor with anyvdesired degree of pressure, of course Within certain limits, depending upon what is most advantageous under the particular circumstances, the arrangement being such that the clamping block may be objectionable for obvious reasons. In some types point which is well recognized is that for sup.

said to float with the conductor, the weight of the latter being sustained by only the end portions of the main clamp body or stirrup-like member, these supporting portionsbeing specially designed for the purpose and in such manner as to avoid any mutilation of or other damage to the conductor. f l

Another object of the invention7 is to provide a clamping block construction in which the effective clamping length may be varied while not 55 altering the actual length.

A further object of the invention is to provide a clamp structure of thisL character in which adaptation for use with .conductors of widely differing diameters is eiected by the simple expedient of employingclamping blocks having bores of diierentA corresponding diameters, it being unnecessary to make any changes in the size or weight of the main body or support.

An additional object is to provide a clamp of this character and having the above pointed out advantages and which will yet be extremely simple and inexpensive to make, easy to apply, positive in action, eiiicient and durable in service, and a general improvement in therart. 3 To the attainment of the foregoing and other objects and advantages, the invention preferably consists in the details of construction and the arrangement and combination of parts to be hereinafter more fully described and claimed, and 35 illustrated in the accompanying drawing in which: l

Figure l is a side elevation of my clamp showing it applied to a conductor, A

Figure 2 is a top plan view, and Figure 3 is a cross section taken on the line 3 3 of Figure 2. 'Y Referring more'particularly to the drawing I have shown my device as comprising a main clamp body or support indicated as a whole by the numeral 10. This body is of general channel shape in cross section with its end portions 11 grooved to form curved seats 12 for the conductor 13, and with its central portion depressed or downwardly offset as at 14 so as to be out of 'contact with -the conductor which is consequently supported only at the two points 12. From these bearing seats the end portions are iiared downwardly as at 15, or bell-mouthed, so as to avoid contact with and the bringing of bending strains upon the cable. The central portion 14 is of greater width than the end portions 11 and constitutes a 'socket for the reception of theclamping block device indicated as a whole by the -numeral 16 which simply ts loosely. 'Ihe sides of the central portion 14 are extended outwardly at opposite sides of the center to denne recesses 17 for a purpose to be described.

A clamp of this general type is primarily intended to be suspended and simply for purposes apertured ears 21 by means of which connection made., be made at the lower end of a string of insulators, not shown,.by the employment. of a bolt for the purpose. The ends of the trunnions are preferably formed with downwardly extending heads 22 which overhang the lower ends of the openings in the links and which operate to prevent separation of the parts. As an additional precaution in this respect, cotter' pins 23 may be passed through the trunnions outwardly of the links. While this particular mounting is shown and described it should be understood that the invention is not limited thereto as some other supporting means might'be provided if found preferable for any reason.

The clamping block member 16 is formed of separable sections 24 and 25, .the former being the lowerl and the latter the upper,which are grooved, channeled, i recessed 'or otherwise ,shaped to conform to the cross sectional curvature of the conductor. These membersV are held in clamping relation to the cable by means of bolts 26 which pass through enlargements 27 and 28 at the corner portions of the separablev members, these boltsbeing represented as each carrying `a .washer 29 and having screwed thereon a pair of nuts 30 and 30* between which is `an addi- .tional washerv 31. The .bottom of the central portion 14 is formed with openings 32 for the passage of the washers 29 and nuts 30A but it will be noted that the washers 31 are of greater diameter than the openings 32 so as to prevent the block device 16 from rising out of the socketed central portion 1'4 of the main body. The underside of the member 24 isv shown as having a slight boss or projection 33, at each-opening 32,- and the upper member 25 hasfits top surface formed with shoulders 34 against which the heads of the bolts 26 engage andA which therefore operate to prevent the bolts from rotating while the nuts are applied or' removed as the case may be. The lateral enlargements 27 and 28 on the members 24 and 25 respectively are received within thel point, the bolts 28 arepassed through the members 24 and 25, with the heads of the bolts engaging at one edge against the respective shoulders 34, subsequently to which the washers 29 and nuts 30 are applied, the latter being screwed ydown as tightly as may be necessary to bring l about the desired degree of clamping action. The

main body or stirrup member is then placed in ,position beneath the block device 16 and mnved upwardly with respect thereto so that the lower through the-openings 32, the block device 16 then tting loosely within the central portion 14 of the supporting body. The washers 31 and nuts 3()n are applied, the washers 31 manifestly acting to prevent lateral .separationor vertical separa= tion of the main support and clamping block device. The links 19 are then engaged upon the trunnions 18 and moved upwardly and toward each other and connected with the insulator string, not shown, by means lof a conventional bolt which is likewise not illustrated as it forms no part of the present invention. The final step is to apply the cotter pins 23 which may not be vitally important but .which are an additional safeguard to preventthe links from disengagement withthe trunnions.

When the device is assembled in this manner it -is apparent that the block device 16 will be spaced above the bottom of the depressed central portion of the stirrup-like main body and that the conductor will itself rest upon the curved l seats 12. The block device 16 cannot move longitudinally with respect to the main body 10, is incapable of. lateraldisplacement with respect thereto in a horizontal direction and has its vertical movability limited by the washers 3l. Naturally under ordinary circumstances the weight of the cable is entirely adequate to hold it down in place but in casel of some undulatory movement of the cable it is conceivable that the block device 16 might rise to the limited extent indicated which, however, would cause no harm. The

point is that the block device 16, or clamping block whichever it may be called, fits loosely within the main body of the clamp so that the conductor will not be rigidly restrained in the clamp body but will lie loosely in it. As the clamping block 16 is relatively small and may possibly be formed of cast aluminum, it will be very light and will have but little eiect on the `conductor so that the latter may move quite freely with respect to the main body of the clamp. The point of advantage lis that the clamping block is easily capable of being made accurately as far as its nt on the conductor is concerned so that a deilnlteI and precise holding power may be obtained. The holding power of course may be readily varied by varying the length of the clamping block, that is to say the effective length and not the actual length and this may readily be done by counter- 1 boring the ends so as to reduce the area in actual contact withj the cable. Whether the ends be counterbored or not, it is preferable that they be somewhat flared or bell-mouthed for the protection of the conductor strands.

From the `foregoing description and a study of the'drawing it will be apparent that I have thus provided a very simply constructed and easily assembled and applied clamp which will be eilicient=in its holding action and which will entirely avoid mutilation ofthe conductor. It is thought that the construction, operation and advantages should be apparent to one skilled in the art without further explanation.

While I have shown and described the preferred embodiment of the invention, it should be understood that the disclosureis merely an exemplication of the principles involved as the right is reserved to make all such changes in the details of construction as will widen the field of utility and increase the" adaptability of the device provided such changes constitute no departure from the spirit of the invention or the scope of the claims hereunto appended.

l5, ends of the bolts 26 and the nuts 30 will pass Having thus described the invention,Iclaim: 159

1. A suspension clamp comprising a main supporting body. having means for mounting tne saine, and vertically movable means adapted to be tightly clamped upon a conductor and fitting loosely within said main supporting body, whereby the conductor will simply rest gravitation ally upon the supporting body.

2. A suspension clamp comprising a main supporting body having means for mounting the same, and retaining means adapted to be tightly clamped upon a conductor and to it loosely within said main supporting body, with the conductor resting upon the latter, said retaining means being restrained from all movement other than vertical with respect to said supporting body. I

3. A suspension clamp for a conductor, comprising a main supporting body having means for mounting the same, and having spaced seats upon which the conductor may rest, and means rigidly clamped upon the conductor and iitting loosely within said main supporting body in spaced relation to the bottom thereof and operating to prevent longitudinal movement of the conductor with respect to the main supporting body while enabling the weight to be borne entirely by said seats.

4. A conductor suspension clamp comprising a main supporting body having conductor support- .ing seats at its opposite ends and having a socket between said seats, and means adapted to be rigidly clamped upon the conductor and tting loosely within said socket.

5. A conductor suspension clamp comprising a main supporting body having a conductor receiving channel therein, said channel being formed to provide conductor seats at opposite sides of the transverse center, an enlarged socket in the body between said seats, and a blockdevice adapted to be rigidly clamped upon the conductor and'tting within said socket.

6. A conductor suspension clamp comprising a main supporting body having means for pivotally supporting the same, said body having a conductor receiving channel and being centrally widened and deepened to provide a socket, seats at the opposite ends of thesocket, and a separable blocklike clamp engaged upon the conductor and fitting within said socket.

1. A conductor suspension clamp comprising a main supporting body having means for pivotally supporting the same, said body having a conductor receiving channel and being centrally widened and deepened to provide a socket, seats at the opposite ends of the socket, and a separable blocklike clamp engaged upon the conductor and fitting within said socket in spaced relation to the bottom thereof.

8. A conductor suspension clamp comprising a main supporting body having means for pivotally supporting the same, said body having a central socket opening upwardly and provided in its bottom with openings, the body having channeled conductor engaging seats at the opposite ends of the socket, a sectional block-like member prou vided with bolts for clamping it upon the conductor and fitting loosely within saidsocket with said bolts passing through said openings.

9. A conductor suspension clamp comprising a main supporting body, suspension means therefor, said body having channeled conductor receiving portions and provided centrally with a socket with spaced outwardly projecting sides, the body having conductor engaging seats adjacent the socket, and means secured upon the conductor and iitting loosely within the socket in spaced relation to the bottom thereof to enable the weight of the conductor to come upon said seats, said means comprising separable parts bolted to- 10. Means for supporting a conductor, comprising a member clamped rigidly thereon in surrounding relation thereto, and a supporting body equipped with suspension means and formed with seats adapted to engage against only the underside of the conductor, said body having a recess receiving said member for preventing longitudinal movement thereof with respect to the body.

11. Means for supporting a conductor, comprising a separable clamping member rigidly secured thereupon and a supporting body equipped with mounting means, said body having an open central portion receiving said clamping member and cooperating with 'the ends thereof to prevent relative longitudinal movement, said body being formed outwardly of the central open portion with seats engaging against the underside of the conductor.

12. Means for supporting a conductor, comprising a clamping member rigidly secured thereabout, and means located beyond the opposite ends of said clamping member and engaging against the underside of the conductor by gravity of the latter, said means cooperating with said clamping member for preventing longitudinal movement thereof and consequently the conductor with respect to said means, said clamping member being capable of vertical movement with respect to said means.

13. A conductor suspension means comprising a main supporting body provided with conductor supporting seats, and keeper means rigidly clamped upon the conductor and fitting within said body in unsecured relation thereto in spaced relation to the seats.

14. A conductor supporting means comprising a main supporting body having portions directly engageable beneath the conductor and gravitationally supporting the same, and means secured upon the conductor and received within the body in unsecured relation to the latter for restraining the conductor against longitudinal movement with respect to the body.

15. A suspension clamp comprising a supporting body equipped with suspensionmeans and having stops at opposite sides of its transverse center, retaining means adapted to be secured upon a conductor and to flt within said body between said stops with the conductor engaged upon the body beyond the stops.

ROBERT L. MCCOY. 

